Wireless communication networks are widely deployed to provide various communication services such as telephony, video, data, messaging, broadcasts, and so on. In many different scenarios, such as for the transmission of images or streaming video media, it is desirable to resize the images. Some conventional methods of resizing an image to a different (larger or smaller) size include image scaling, downsampling, and cropping to remove pixels around the boundary.
Another method for image resizing, known in the art, is called seam carving. Seam carving may be referred to in the literature as image retargeting, content-aware image resizing, content-aware scaling, liquid resizing, or liquid rescaling. Seam carving can be advantageous over other image resizing methods, as it enables consideration of the image content, not just geometric constraints, thereby providing a content-aware resizing of an image. A seam is a connected path of low-energy pixels, which crosses an image from top to bottom, or from left to right, etc. Seam carving can be utilized to resize or retarget an image by carving out or inserting pixels in different parts of the image. Seam carving generally utilizes an energy function, defining an “importance” of the pixels of the image. By successively removing or inserting seams, the size of an image may be reduced or increased, respectively.
For image size reduction, seam selection ensures that while preserving the important image structure, more of the low energy pixels may be removed, and few of the high energy pixels may be removed. For image size enlargement, the order of seam insertion ensures a balance between the original content and the artificially inserted pixels. While seam carving is known in the art, there is still room for improvement in the process, e.g., in terms of computational efficiency, as well as for image quality, especially relating to video retargeting (resizing of video streams).